Fei Bao SU-27 User manual

DISCLAIMER:
THIS IS NOT A TOY. This is a high-performance
miniature aircraft, capable of high speeds and damage to
life, limb, and property. The manufacturer and its
distributors cannot control how you assemble this model,
what equipment you use to fit it out, or how you fly it, and
can assume no liability whatsoever for any damages that
may occur when you fly your aircraft. By assembling this
model, you are agreeing to indemnify and hold blameless
the manufacturer and/or his agents from any and all torts
and liability associated with the use of this product.
Please inspect all parts before beginning assembly. If
any parts appear to be suspect, contact your dealer or the
manufacturer for repair or replacement BEFORE you
begin. Once you have assembled the aircraft, you are
the pilot in command and assume any and all
responsibility for the use of the model and any damages
that might occur by flying or attempting to fly this aircraft.
R/C model jets require a high level of skill in both their
assembly and their flying. If you do not feel confident in
either your building or flying skills, PLEASE seek
assistance from more experienced modelers. It is a wise
idea, no matter what level of skills you possess, to have a
second experienced modeler go over your installation
after assembly. A second set of eyes may spot a problem
you have missed. If you have not flown a model like this
before, it is HIGHLY recommended that you get an
experienced turbine pilot to do your maiden flight. Very
often, the first few seconds of a maiden flight are critical
until the aircraft is trimmed out, and having an
experienced pilot at the controls can make the difference
between a wrecked aircraft and once that enjoys many
hundreds of flights. Be sure to select a suitable field for
flying...take the time to find a large paved runway if at all
possible, especially for test flights, until you feel
comfortable getting the aircraft in and out of smaller grass
fields.
BEFORE YOU BEGIN:
Keep this in mind as you proceed:
Look at EVERY assembly step you finish, and ask
yourself:
"Is this going to crash my airplane?"
A chain is only as strong as its weakest link, and this is a
high-performance aircraft that will be very intolerant of
sloppy assembly techniques. Even the smallest
component is important and can cause the loss of your
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airplane, so take the time to do things right. Or REdo
them if they are wrong. Careful work will result in a long-
lasting plane that gives you years of pleasure, one loose
component could result in the complete loss of the aircraft
and all the components inside it, and someone can even
get hurt. So pause every once in a while when building it
and double-check your workmanship.
A. Introduction:
You have chosen a model that represents the pinnacle of
ARF technology. While there is not a lot of building to do,
there is enough to keep you busy for a few evenings.
Even if you have assembled maybe other ARF jets, we
highly recommend following our assembly sequence and
procedures anyway.
Chances are it will save you a lot of time, prevent you
from running down dead ends, and perhaps remind you
of a few small things that might end up saving your
aircraft.
We have tried to arrange a construction sequence that
will allow you to keep moving forward, rather than
standing around waiting for glue to dry before you can
proceed to the next step.
Just because the model is almost completely built does
not mean you can rush through the final assembly.
You need to employ fine craftsmanship every step of the
way, turbine models are critical. Keep this in mind with
everything you do, every part you install...look at the work
you just did, evaluate it critically, and ask yourself "is this
going to potentially crash my airplane?" If there is any
doubt about the work you have done, back up, and re-do
it properly.
B. Adhesives:
The correct adhesive to use for all procedures is Loctite
Hysol 9462. This is a very strong white epoxy that is
thixotropic. "Thixotropic" means it does not run at all, but
stays only where you put it. It is infinitely superior to
regular epoxy, even slow-setting epoxy, for our purposes,
because of this characteristic.
Regular epoxy will run downhill with gravity as it dries,
taking it away from where it is supposed to be.
A good example is in the hinges...using regular epoxy, a
good portion of the glue will migrate down away from the
hinge into the inside of the wing as it dries, and you won't
even know it is happening. Hysol stays where you put it.
The downside of Hysol is it takes overnight to dry
properly, but we have tried to arrange things to keep you
busy while waiting for glue to dry.
We also highly recommend that you only use a proper
Hysol dispensing gun, and only the long-type mixing
nozzles.
The short nozzles do not mix this glue enough, and only a
thin nozzle and gun will let you fill the hinge and control
horn holes properly with glue, you can't do it mixing your
Hysol on a flat surface and trying to get the glue in the
proper place by a brush or stick.
You can buy a complete Hysol setup with a gun, nozzles,
and two cartridges of glue from your dealer for
approximately $60.
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Consider it a great investment, the glue is the best you
will use. One cartridge is plenty to assemble your aircraft.
C. WORKING WITH PNEUMATIC SYSTEMS:
The T45 uses pneumatic brakes and retracts. If you
follow a few tips, you should have very reliable, leak-free
operation. Neatness counts.
All airlines should be secured to the airframe to keep
them from flopping around or getting kinked. Use tie
wraps for this.
The other very important thing is to cut off the end of each
airline dead square before installing it on the nipple.
This is VITAL. You can either purchase a professional
tubing cutter from your dealer (they are approximately
$10), or you can make up a little jig to hold the airline and
keep a sharp, new razor blade perfectly upright as you
cut.
Either one works, just ensure that all ends of all airlines
are cut off dead square. Make sure all airlines are
pushed ALL THE WAY onto their nipples.
They should not need to be secured otherwise, but you
can add fine wire safety wraps if you like. Make sure all
left and right matching airlines are the same length,
particularly the brake lines, or you will get uneven
retraction or braking action.
It's worth taking the time to get everything pneumatic right
the first time, as having your landing gear fail to retract is
not THAT bad, but having it fail to deploy can really ruin
you day and the paint on the bottom of your model.
Sample Servo List:
Rudder: JR 3301 (2)
Flaps: JR 8611A (2)
Elevators: JR 8711 or equivalent (Use highest torque
servos available)
Nose Gear Steering: JR 8411 or JR 2721
Air and Brake Systems: As necessary
Parts List:
•Forward Fuse with Component Boards and Nose Gear
•Pitot Tubes (2)
•Aft Fuse, Main Landing Gear
•Parachute Stinger
•Canopy
•Cockpit Tub and Glare Shield
•Main Upper Hatch with Speed Brake
•Left Intake
•Right Intake
•Wings, Flaps
•Vertical Stabs (2), Rudders (2)
•Ventral Strakes (2)
•Fuel Tanks
•Pipes (2)
•Air Kit
•Hardware Kit
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Notes
These instructions were written based upon the
prototype kit from the Fei Bao factory. Please
note that the kit and components may have
undergone changes through the production
process. Center of Gravity and control surface
throws were confirmed as a good starting point
through limited flight testing, but it is important
that you contact your Fei Bao representative prior
to your first flight to obtain the most current
information on these important parameters.
Begin construction by prepping the airframe
If already assembled, remove the bypass
modules from the airframe (see photo). They
are attached by two bolts accessed through the
hatch on each side.
Remove the engine hatch covers, marking
them for side and orientation as you do so.
Using a hand pump and a short piece of tubing,
check each of the gear door air cylinders for
leaks. If they hold air under pressure, secure
the nuts and bolts attaching the cylinders to
the fuselage and doors with a small drop of
thin CA.
Insert the stabs, wings and vertical stabs into
their respective mounts. Check each mount for
security, tightening bolts and nuts if necessary.
it is recommended that you run a bead of
Aeropoxy around the mounts to secure them
firmly in position on their formers.
Check all accessible areas for the integrity of
glue joints and add Aeropoxy if necessary. Pay
special attention to the formers that secure the
horizontal stab bearings, adding glue to make
sure they are firmly affixed to the fuselage.
Take care not to get any glue into the bearing
components.
Join fuselage halves and bolt securely in five
places.
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Air systems
Remove the nose gear from the aircraft.
Using a Matchmaker or a receiver and your
transmitter, center the nose steering servo and
attach a heavy duty steering arm.
Bolt in the nose gear steering servo as shown
in the photo. Do not use the rubber mounts
and brass eyelets. Loctite the bolts.
While the nose gear is out, make sure there are
no kinks or bends in the air lines.
Check the security of all screws and C clamps
on the struts and retract units.
Option: If your nose and main gear were
attached to their mounting plates by wood
screws, you may opt to reattach them with cap
head bolts and blind nuts. If so, remove the
mains, drill and install blind nuts for all three
landing gear, and reinstall.
Once the nose gear is reinstalled, operate the
strut by hand and insure that the nose gear
door will close completely over the nose wheel
mud guard. If not, shim the retract unit with
washers or ply until the door closes.
It is recommended that you install your air
systems for doors, retracts, brakes and speed
brake on the removable board in the nose of
the aircraft. Remove the board, paint if
desired, and install servos and valves. Make
sure to allow clearance to the sides of the
board for the curvature of the nose section.
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The receiver may also be installed on this
board.
As the three main gear all retract forward, you
may wish to provide more air to each unit. To
accomplish this, set up the nose gear on one
air valve designed for large scale aircraft and
supply air to the mains from a second,
separate valve. Use separate air supplies for
each. Run separate lines to each main from
the valve ... do not “T” from a single supply.
Make sure to pull up the landing gear before
the aircraft picks up speed after liftoff.
As you position these components, make sure
to leave room for the cockpit installation.
You will need to supply sequencing for the
doors. On the full scale aircraft, all doors
remain open with the gear extended.
Run air lines to all the door cylinders, the
retracts, the brakes and the speed brake.
Hook up fill valves, air meters if used and
supply tanks.
Test the system for operation and leaks.
Adjust as necessary.
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Horizontal Stabilizers
Using a Matchmaker or receiver and
transmitter, center both horizontal stab servos.
Install the servo arms such that they are
matched as closely as possible for both servos.
Option: for added security, use metal servo
arms for this application. If you use a tapped
metal servo arm, you will need to replace the
clevis supplied with the kit with an appropriate
ball link. You can secure with a small amount
of CA for extra security. See photo.
Install servo into its mount, securing with four
screws. Do not use rubber mounts and brass
eyelets.
To keep the heat away from the servo during
engine operation, make a small shield that can
be bolted to the formers. In the prototype,
BVM heat insulation covered by aluminum tape
was used. Leave some space for air
circulation. See photo on following page.
Insert stab spars into control arms, using large
Delrin washer for spacing from fuselage. Hold
pressure against fuselage and tighten allen
bolts securely. Check for smooth operation and
minimal play.
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Using a cutter, open up a small hatch above the
servo opening on the upper rudder mount
platform in order to access the servo arm. See
photo. Make up two servo linkages of exactly
the same length.
Install linkages on to the servo arms and
bearing box control arms.
Check to make sure horizontal stabs have full
movement on both top and bottom. Adjust
and trim material around the stab control arm
as needed to achieve full throws.
Test fit the vertical stab in place. You may
need to trim the lip around the bottom of the
opening to provide control arm clearance.
Check linkage cover for adequate clearance.
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Vertical Stabs and Rudders
Begin by gluing rudders into vertical stabs as
follows: fill the hinge point holes in one
vertical stab with a generous amount of
Aeropoxy. Insert rudder. Install vertical stab
into the fuselage and temporarily tighten
mounting bolts. Move the rudder inward to the
point where it just contacts the exhaust tube
on the fuselage. Press the rudder forward such
that it contacts the hinge cover equally along
its length. This will set the appropriate depth
of the hinges. Visually check for even spacing
along the length of the hinge line.
Repeat for the other side.
When the glue is dry, remove the vertical
stabs.
As with the elevator servos, locate neutral and
install servo arms.
Drop the servos into their pockets, oriented as
shown, route servo wire to the bottom of the
rudder, and secure with screws. Use masking
tape on the drill bit to make sure you do not
drill all the way through the stab when
installing screws.
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Open up the slot in the rudder with a small
cutter and Dremel tool for the control horn. Be
very careful not to cut through the rudder as
you enlarge the slot.
Optional: paint the control horn to match your
color scheme.
Tape around the slot with low grip masking
tape and fill the slot with Aeropoxy.
Rough up the gluing surface of the control horn
and insert into the slot. Make a nice fillet
around the horn, and then remove tape. Allow
to dry thoroughly.
Repeat for other vertical stab and rudder.
Prepare and install linkages.
Trim hatch cover to clear linkage and arm, then
reinstall.
Reinstall vertical stabs permanently, tightening
two clamp bolts per side.
Now is a good time to install servo extensions
to the elevator and rudder servos. Make sure
they are fastened securely away from the
exhaust pipe area.
Exhaust Cones
If the exhaust cones are not already installed,
slip them over the bolts on the rear former and
rotate unit until the bolts seat in the slots.
Tighten bolts securely.
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Wings
Fill the hinge point holes in the flap leading
edge with a generous amount of Aeropoxy.
Insert the flaps and press forward to the point
that you achieve approximately 45 degrees of
throw.
As you did with the Elevator and Rudder
servos, find center and install servo arms in
horizontally opposing locations.
Option: use metal servo arms for this
application. If you do, you will need to use ball
ends as you did for the elevator linkages.
Install servos in wing, using screws. Do not
use rubber mounts or brass eyelets.
Carefully measure the distance to the servo
arm, and mark position on the bottom of the
wing. Double check your calculations, and if
satisfied, drill a small pilot hole at this location.
If located properly, open up a slot for the servo
arm.
Mark the slot location on the flap for the control
horn, using a 90 degree square to insure it is
perpendicular to the hinge line. Line it up with
the servo control arm. If you are using a clevis
on the servo arm rather than a ball link, allow
for some offset of the ball end that will attach
to the control arm.
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Open up the slot in the flap with a small cutter
and Dremel tool for the control horn. Be very
careful not to cut through the control surface
as you enlarge the slot.
Optional: paint the control horn to match your
color scheme.
Drill the control arm for the ball end bolt. Start
with smaller wire size drills and find the one
that is just large enough for the bolt without
allowing play.
Tape around the slot with low grip masking
tape and fill the slot with Aeropoxy.
Rough up the gluing surface of the control horn
and insert into the slot. Make a nice fillet
around the horn, and then remove tape. Allow
to dry thoroughly.
Repeat for other wing and flap.
Prepare and install linkages.
Run flap servo extensions to receiver location.
Test fit wing to fuselage. Make sure the
inboard root edge of the flap clears the
fuselage in all positions. The part most likely
to rub will be the inboard root edge of the flap
as you move the control surface to its extents.
Tighten wing attach bolts and check for any
play.
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Engine Installation
If you haven’t already removed the engine
hatch covers, do so now, labeling each side.
Completely straighten the taps on each side of
the pipe. Note that the tabs are closer
together on one side, this will be the “bottom”
of the pipe, though it will be oriented “up” as
you work on the aircraft upside down.
Note: if you are using a bypass, mount the
pipe to the aft end and drill tabs and bypass for
mounting bolts. Reinsert pipe in fuse aligning
aft end with the rear of the exhaust cone,
position bypass on rails and secure pipe to
bypass with bolts. Skip the remaining steps on
this page.
Insert the pipe into aft former.
Align aft end with the rear of the exhaust cone.
Mark the tabs about 1/4 inch in front of the aft
engine mount former.
Remove pipe and drill a 1/16 inch hole at the
marks. A drill press will make this job go
quickly.
Reinsert the pipes.
Using scrap ply, make a triangular mounting
plate glue securely between the engine rail and
the aft engine mount former. See photo.
Do not attach pipe tabs to this mounting
former yet. This will be completed once the
engine is in position.
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Position the engine on the mounting rails. If
need be, make a supplemental mounting plate
if the engine tabs do not completely span the
gap between the rails.
Confirm that the engine to pipe clearance is set
at manufacturers specifications, drill and bolt
the engine to the rails.
Check the angle of the engine and make sure it
follows the slope of the exhaust pipe. You may
need small shims under the front tab to
achieve the appropriate angle.
Raise the pipe, check to make sure it is
centered on the engine exhaust cone, and
permanently attach the tabs to the triangular
plates.
Repeats steps for other engine.
On the prototype, the engine valves and fuel
pump are located on either side of the fuel tank
compartment, in the center section adjacent to
the main wheel when retracted, underneath the
fuse side. See photos on the following page.
Make sure to tape all extensions securely.
On the prototype, the ECUs were attached with
Velcro to the main center tank for ease of
access. See photos in the fuel system section.
Run wiring, fuel and gas lines to these
positions.
Insert intakes temporarily to make sure there
is adequate clearance for tubing and wiring.
Leave off the engine covers for now to avoid
cracking them as you complete construction.
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Cut a valve/pump mounting plate out of scrap
ply, approximately 2 inches wide by 6 inches
long.
Mount components as shown in the photo.
Make a mirror image arrangement for the other
side.
Using velcro, temporarily position plates in the
wheel bay, making sure that there is adequate
clearance when the main retracts. Make sure
the main tank will fit in its bay.
You may hook up the fuel and gas lines to the
engine at this time. Insert intakes temporarily
to check for adequate clearance of the various
lines. Don’t forget the manual shut-off valve.
Fuel System
In the prototype, two additional tanks were
positioned in the area behind the main tanks to
increase overall fuel capacity by another 25
ounces. Production kits may have a different
tank configuration, but if not, the auxiliary
tanks may be obtained from JetTech. Make
sure to order them without the clunk opening
cut out ... you will do this yourself once the
tanks are in.
To install the aux tanks, you will slide them up
through the intake opening on the underside of
the aircraft. They may need to be extended
slightly to provide clearance. The rear hatch lid
may also need trimming.
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Temporarily position the intakes in place to
make sure you have clearance. See photo.
Once everything is in place to your satisfaction,
mark the pickup and vent fixture positions.
Remove the tanks, plumb, leak check and
reinstall.
Drill fuse for vents and plumb. See photo.
At this time, permanently reinstall the intakes,
making sure no lines or wires are pinched or
kinked, securing with two forward intake attach
bolts. Make sure they engage the blind nuts
fully, but do not penetrate the inside of the
intake. It is important that these two bolts be
attached securely.
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If you are using UATs, it is recommended that
they be positioned in the forward fuse, flanking
the nose gear cylinder.
Make a platform as shown in the photo and
affix to the forward former with a large piece of
industrial velcro.
Disassemble the main tank stoppers and check
for kinks, obstructions and secure connections.
Option: for added security, drill and tap
aluminum fittings for 6-32 cap head bolts. It
will be easier to tighten these down.
Both main tanks will face forward. The aft
main tank will need to have the pickup lines
bent to clear the forward main tank.
Reassemble both main tanks and leak check.
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The ECU batteries fit nicely into the pockets on
either side of the forward main tank. Wrap
them in foam and insert, padding with extra
foam as needed. Watch wiring and air lines.
Install and plumb main tanks, running pickup
from aux tanks to the vents of the mains, and
the pickups from the mains to the UATs. The
UATs will then connect to the pumps.
Keep all fuel lines for both sides of equal
length. Loop where necessary.
Block tanks with foam ... they will be a snug fit
and should not need any further attach
mechanisms.
Position ECU units as shown and complete
wiring.
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Completing Construction
Glue ventral fins in place. It is recommended
that you faintly draw the outline on the fuse
and then drill a number of attach holes for the
glue to use to “pin” the fin securely in place.
Make sure the fins are positioned at equal
angles. Use a straightedge as shown to check
for equal spacing on both sides.
Install the aft fuse strake, attaching with two
bolts from underneath the fuse.
Glue the pitot tubes to the forward fuse on
either side of the cockpit.
Reattach the engine covers.
Tape or use a flexible cement to install glare
shield in cockpit. Install pilot in tub if desired,
and drop tub into place.
Check the fit of the canopy and adjust as
needed.
This completes primary assembly of your SU-27
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Throws and CG
The CG and throw recommendations in this
manual were based upon limited test flying.
Please check with the manufacturer for current
information before flying your SU-27 for the first
time.
For the first flight, set the CG at approximately
8.5 inches aft of the wing/fuse junction at the
leading edge, measured aft along the wing/fuse
joint. For an easy method of precisely calculating
CG on large aircraft such as the SU-27, visit the
Jet Pilots Organization website www.jetpilots.org
and access the weight and balance spreadsheets
under the “members” tab. You will find
instructions on how to use the spreadsheets there,
as well as the data used to balance the prototype
FB SU-27. You will need to fine tune the CG as
you fly the aircraft based upon your fuel tank
configuration and personal tastes, so keep this in
mind as you install any ballast.
Measure the CG with residual fuel and the gear
lowered.
Maximum throw on the elevons measured at the
leading edge is 40 mm for elevator function, with
30 mm for aileron throw. Set as much rudder
travel as you can without binding.
It is important that you set three rates for
elevator and aileron, using the recommended
throws as the mid position, with settings higher
and lower. In this fashion, you can quickly set the
throw to your personal flying taste and habits on
the first flight. We used 40% exponential on the
first flights for both aileron and elevator.
For first flights, have the flaps on a slider control,
such that flaps can be incrementally deployed.
First Flights
•Do not attempt a first flight in adverse weather
conditions.
•Make sure there are no known issues with the
airplane before attempting the flight.
•Have a qualified spotter handy to help you with
trim and rate switches on the first flight.
Designate a third individual as a timekeeper.
•Leave the gear down on the first flight.
•Advance the throttles slowly but fully, and keep
the turns shallow at first.
•Focus first on trim and rate. Establish these on
the first few laps.
•Take the plane to a safe altitude and become
comfortable with slow speed handling. Carefully
deploy the flaps, looking for any loss of control in
roll or pitch as you do. If you experience any
issues in this regard, back off the flap setting
until the problem abates.
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